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Heatwave Turns Cars Into Ovens

Scorching heat causes discomfort, power outages across most of US

California’s Record-Breaking Storms Trigger Flash Floods

Nightly News
July 20, 2015

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TODAY
July 20, 2015

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>>>good evening from
nova scotia
west to michigan, south to virginia, cities and towns and people are all under strain because of the hottest temperatures of the summer and what is now the longest duration
heat wave
in a decade in some places. the system causing it just continues to sit there, while millions bake beneath it. for a lot of the
east coast
, cities like philadelphia, this week, right now, is traditionally the hottest week of the year every year. and this year has decided not to disappoint. we have it all covered tonight from the widespread heat to the forecast ahead to the latest and largest heat-fed wildfire out west near
palm springs
. we begin tonight with nbc's tom costello on the
national mall
. tom, good evening.

>> reporter: hi, brian. we got up to 102 today with the
heat index
in washington. hottest day of the year in chicago. a lot of cities haven't seen
heat waves
like this in years. boston expected to break a record that goes back to
1997
. and amtrak this evening says it has got disruptions on the
northeast corridor
because of heat that will likely inconvenience tens of thousands of customers. 'tis the season, but boy, is it hot outside. add in the humidity and the heat indices are at or near 100, from the
lake shore
in chicago to the streets of minneapolis. from the carolinas to new england.

>>i come out thinking i'm going to run as as far as i usually do, but then i hit the heat and i think, well, let scale that down just a little bit.

>> reporter: in new york, two children and nine firefighters were taken to area hospitals after a fire in suffocating temperatures last night.

>>has various vapor barriers that keep the heat in and have to relieve quite often and make sure we hydrate them.

>>this dome of hot air,
high pressure
, which means the air is sinking.

>> reporter: this
heat wave
is extending across the country. 45 states experiencing temperatures in the 90s or above. many cities five to ten degrees above average. new
york city
could see the longest stretch of 90-degree weather in 11 years. even hotter for the guys working the city food carts.

>>terrible. i sweat like a chicken, you know?

>>we need to drink a lot of water.

>> reporter: after three days of extreme heat in d.c., doctors at med star
washington hospital center
are starting to see
heat stroke
patients.

>>whether you're a worker with physical exertion or an athlete out there, you got to take breaks. you got to take water breaks. you got to take cooling breaks. you got to get out of the sun.

>> reporter: there is good news those for hundreds of people in maryland's
prince georges county
who thought they would be without water through the weekend. crews say they can fix the
water main
without turning off the water. out on the streets, making a buck means sweating a bucket.

>>i need sunscreen, i need sunglasses, i need this hat and i need gatorade, man.

>> reporter: this is david landerman's first week pedaling a cab. timing is everything. we checked on the status of the
power grid
. they tell us it's holding up well. in fact it would have to get even more hot, even more humid for longer stretches of time before the
power grid
would in any way be considered to be unstable. brian, back to you.

>>still getting over the image of that vendor sweating like a chicken. not swhur what that means. tom costello in washington starting us off tonight. tom, thanks.